RIO DE JANEIRO (AP) — A British journalist and an Indigenous affairs official were still missing in a remote part of Brazil’s Amazon on Tuesday as authorities said they were expanding search efforts in the area, which has seen violent conflicts between fishermen, poachers and government agents.

Dom Phillips, who has been a regular contributor to the British newspaper The Guardian, and Bruno Araújo Pereira were last seen early Sunday in the Sao Rafael community, according to the Univaja association of people in the Vale do Javari Indigenous territory, for which Pereira has been an adviser.

The pair was returning by boat to the city of Atalaia do Norte, about an hour away, but never showed up.

Pereira is one of the Brazilian Indigenous affairs agency’s most experienced employees operating in the Vale do Javari area. He oversaw the agency’s regional office and the coordination of isolated Indigenous groups before going on leave. He has received a stream of threats from illegal fishermen and poachers, and usually carries a gun.

Univaja said the two had been threatened during their reporting trip. On Saturday, while they were camped out, a small group of men traveled by river to the Indigenous territory’s boundary and brandished firearms at a Unijava patrol, the association’s president, Paulo Marubo, told The Associated Press. Phillips photographed the men at the time, Marubo said.

Phillips, 57, has reported from Brazil for more than a decade and has been working on a book about preservation of the Amazon with support from the Alicia Patterson Foundation, which gave him a yearlong fellowship for environmental reporting that ran through January.

The pair disappeared while returning from a two-day trip to the Jaburu Lake region, where Phillips interviewed local Indigenous people, Univaja said. Only the two were on the boat.

The place where they went missing is the primary access route to the Vale do Javari, Brazil’s second-largest Indigenous territory, which is bigger than Maine and where several thousand Indigenous people live in dozens of villages. People from the area say that it is highly unlikely the men would have gotten lost in that sector.

“He is a cautious journalist, with impressive knowledge of the complexities of the Brazilian environmental crisis,” Margaret Engel, the Alicia Patterson Foundation’s executive director, wrote in an email. “And he is a beautiful writer and a lovely person. The best of our business.”

Brazil’s federal public prosecutors said in a statement Monday that they had opened an investigation and that the Federal Police, Amazonas state’s civil police, the national guard and navy had been mobilized. The navy, which prosecutors described as coordinating the search, said it sent a search-and-rescue team of seven and would deploy a helicopter Tuesday. There were no reports of helicopters being used at any point on Monday, and many of the men’s colleagues expressed concern that the government didn’t appear to be acting swiftly.

“We request from the authorities speed, seriousness and all possible resources for that search,” Pereira’s family wrote in a statement. “Every minute counts, every stretch of the river and the forest not yet checked could be the one where they are waiting for rescue.”

The army’s manpower is far greater than the navy’s in the region, and there was no indication from officials on why it wasn’t included in the initial search efforts. But late Monday, a spokesperson for the army’s Amazon division told AP it had since received orders to deploy a search mission.

Phillips has also contributed to the Washington Post and New York Times. He currently resides in Salvador, a city in Brazil’s Bahia state, with his wife, Alessandra Sampaio, who shared a series of messages posted on Twitter by a journalist helping to advise her.

“I can only pray that Dom and Bruno are well, somewhere, prevented from continuing on for some mechanical reason, and that all of this becomes just one more story in a life replete with them,” Sampaio wrote. “I know, however, the moment the Amazon is going through and I know the risks that Dom always denounced.”

The Vale do Javari region has experienced repeated shootouts between hunters, fishermen and official security agents, who have a permanent base in the area, which has the world’s largest population of uncontacted Indigenous people. It is also a major route for cocaine produced on the Peruvian side of the border, then smuggled into Brazil to supply local cities or to be shipped to Europe.

In September 2019, an employee of the Indigenous affairs agency was shot dead in Tabatinga, the largest city in the region. The crime was never solved.

“It is extremely important that Brazilian authorities dedicate all available and necessary resources to the immediate realization of searches, in order to guarantee, as soon as possible, the safety of the two men,” Maria Laura Canineau, the director of Human Rights Watch in Brazil, said in a statement Monday.

Journalists working for regional media outlets in the Amazon have been slain in recent years, though there have been no such cases among journalists from national or foreign media. However, there have been several reports of threats, and the press has limited access to several areas dominated by criminal activity, including illegal mining, land-grabbing and drug trafficking.

President Jair Bolsonaro issued a comment Tuesday: “Really, just two people in a boat in a completely wild region like that is not a recommended adventure. Anything could happen. It could be an accident, it could be that they have been killed,” he said in an interview with television network SBT. “We hope and ask God that they’re found soon. The armed forces are working hard.”

Three of Bolsonaro’s ministers told the AP on Tuesday that the government recognizes the importance of a swift response, and is concerned that apparent failure to do so will cast a shadow over Bolsonaro’s attendance at the Summit of the Americas this week in Los Angeles. They spoke on condition of anonymity because they aren’t authorized to speak publicly.

___ AP writers Mauricio Savarese in Sao Paulo and Débora Álvares in Brasilia contributed to this report.

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